Ford Super-Duty’s Tow-Behind Virtual Mountain Simulates Steep Hills

If the mountain can’t come to Ford, Ford engineers will build a super heavy-duty mountain simulator and tow it behind the Ford Super Duty. When testing on flat roads of Ford’s Arizona Proving Grounds, Ford engineers use a special dynamometer sled towed behind a Super Duty to simulate traveling up steep mountain grades. The all-new F-Series Super Duty is so powerful that it calls for a new dynamometer sled to simulate steep grades. The dynamometer sled simulates grueling mountain climbs, such as Davis Dam, to test the improved capability of new Super Duty.

Ford engineer Jim Sumner says, “Any test engineer in North America knows about Davis Dam. It’s a demanding hill going from sea level to more than 3,000 feet in 11.2 miles, and is an ideal location to test towing capability. With this dyno we can test the all-new Super Duty on that hill—but from right here on the level surface of our Arizona Proving Grounds.”

Davis Dam is so effective for testing vehicle capabilities that the Society of Automotive Engineers incorporated the grade of the hill into its test standards. Being able to test on this grade without having to make the trip to the real hill in Bullhead City, Arizona, expedites testing and helps Ford engineers ensure that the all-new Super Duty delivers the performance owners expect from their heavy-duty built Ford tough truck.

Traditionally, a dynamometer sled is attached to the vehicle hitch and pulled behind it. The old-style dynamometer did not challenge the power of the all-new Super Duty, so Ford set out to find a new, stronger dyno sled to test the vehicle’s limits. The dyno sled simulates steep grades by providing pull against the vehicle, using a brake limiter (a series of electric coils wired together that are energized, acting like a large magnet). This drawbar pull against the truck mimics gravity while driving up an incline.

Ford’s new dyno sled is capable of a maximum drawbar pull of 5,620 pounds, a 181 percent increase compared with the 2,000 pounds from the previous dyno sled, allowing the new setup to simulate steeper hills. A common simulated grade used for testing is approximately 7 percent, but the new towing dynamometer used at Ford’s Arizona Proving Grounds can simulate up to a 30 percent grade.